Pressing device for the removal of water from cellulose or the like

ABSTRACT

This invention relates to an improvement in a pressing device for the removal of water from solid materials, particularly cellulose or similar fibrous material, comprising pairs of upper and lower horizontal rollers between which a sheet or web of material to be dehydrated is passed on a sieve or between two sieves in a preliminary pressing station, and common bar means supporting at least part of the rollers on one side of said sieve or sieves and being adjustable in the direction toward the sieve. The improvement comprises means pivotally mounting said common bar means at a pivot axis which is pivotal in the direction toward the sieve and which is offset from the center of gravity of the roller axle bearings in the traveling direction of the sieve.

United States Patent Heissenberger 1 Mar. 12, 1974 PRESSING DEVICE FOR THE REMOVAL 2,783,689 3/1957 Skoldkvist 162/358 x OF WATER FROM CELLULOSE OR THE 3,638,562 2/1972 Karaghiosoff 100/170 X LIKE Inventor: I Otto Heissenberger, Graz, Austria Maschinenfabrik Andritz Actiengesellschaft, Graz, Austria Filed: Mar. 27, 1972 Appl. No.: 238,491

Assignee:

U.S. Cl 100/118, 100/1'54, 100/170,

References Cited UNITED STATES PATENTS 7/1902 Graham 100/154 3/1926 Danninger 162/351 X Primary Examiner--Peter Feldman Attorney, Agent, or FirmJames E. Bryan, Esq.

[57] ABSTRACT This invention relates to an improvement in a pressing device for the removal of water from solid materials, particularly cellulose or similar fibrous material, comprising pairs of upper and lower horizontal rollers between which a sheet or web of material to be dehydrated is passed on a sieve or between two sieves in a preliminary pressing station, and common bar means supporting at least part of the rollers on one side of said sieve or sieves and being adjustable in the direction toward the sieve. The improvement comprises means pivotally mounting said common bar means at a pivot axis which is pivotalin the direction toward the sieve and which is offset from the center of gravity of the roller axle bearings in the traveling direction of the sieve.

8 Claims, 2 Drawing Figures PATENIEBIARIZIQM 37196349 SHEH 1 [IF 2 HRESSING DEVICE FOR THE REMOVAL OF WATER FROM CELLULOSE OR THE LHKE The present invention relates to a press or squeezing system designed for the removal of water from cellulose of similar fibrous materials, or other substances, in which a sheet or web of material to be dehydrated is passed, on a sieve or between two sieves, between pairs of horizontal rollers. In presses or squeezing systems of this type, the material which already has been dehydrated to a large extent is futher dehydrated in a preliminary pressing or squeezing station, whereupon the sheet or web of material is passed through the main pressing or squeezing station.

Mounted in the preliminary pressing or squeezing station are a plurality of pairs of rollers between which the sheet of material on the sieve is passed in succession. It is intended that in the pairs of rollers arranged in tandem, and in the traveling direction of the sieve, the pressing effect increase from one pair of rollers to the next pair of rollers. In other words, the contact or bearing pressure of the rollers must increase from one pair of rollers to the next pair of rollers in the traveling or operating direction of the sieve.

Constructions are known in which the rollers of one roller pair are resiliently pressed against each other, independently of the other roller pairs. Such a construction requires, however, a relatively great structural expenditure and moreover a constant supervision or checking of the bearing or contact pressure of the individual roller pairs. It is also known to mount the lower rollers of. all the pairs of rollers on a common bar upon the ends of which latter bearing orcontact forces act, and wherein the contact or bearing force at the other end of the bar, which is positioned at the rear in the operating direction of the sieve, is greater than the contact orbearing force at the end of the bar being positioned ahead in the operating direction of the sieve. This construction also requires a precise adjustment of the pressing forces which must have the proper ratio with respect to each other, and hence a considerable structural expenditure.

The present invention is directed to a pressing device of this type wherein in the preliminary pressing or squeezing station at least a part of the rollers mounted on one side of the sieve and/or sieves are positioned at a common bar adapted to be adjusted in the direction toward the sieve. it is the object of the present invention to eliminate the disadvantages and drawbacks which arise in connection with the known constructions of this type. The bar is pivotally positioned at a pivot axis which is pivotal in the direction toward the sieve and which is offset from the center of gravity of the roller axle hearings in the traveling or operating direction of the sieve. in this manner, the rollers succeeding in the operating direction of the sieve and being positioned on one bar are'more strongly pressed upon than the preceding rollers, and the increase of the pressing effect between the rollers of the roller pairs succeeding each other in the traveling direction of the sieve is assured at a ratio which is determined by virtue of the displacement of the pivot axis of this bar from the center of gravity of the roller bearings. As a result, the entire pressing effect or bearing pressure of all the rollers can be thus set, while the ratio of the bearing pressure or pressing effects of the rollers succeeding one another in the traveling direction of the sieve is determined by virtue of this construction.

According to a preferred embodiment of the present invention, all of the rollers being positioned on one side of the sieve of the preliminary pressing or squeezing portion or station are mounted on a common bar, but the rollers also could be combined with groups within the framework of the present invention, which groups then would be positioned on one bar each in the inventive fashion. It is advantageous for structural reasons within the framework of the present invention to position the upper rollers of the preliminary pressing portion or station in a rigid manner, with the lower rollers at the bar being adjustable with respect to the upper rollers.

The present invention is suitable primarily for the removal of water from cellulose or similar fibrous material, but it also may be employed for the dehydration of non-fibrous materials, such as mud, for example, or foodstuffs.

One embodiment of the present invention is schematically illustrated in the accompanying drawings, wherein HO. 1 is a view of a cellulose dehydrating machine,

and

FIG. 2 illustrates the preliminary pressing or squeezing station atan enlarged scale.

The fibrous material to be dehydrated or freed from water is conveyed or fed between two endless sieves, the lower sieve l and the upper sieve 2, to the cellulose dehydrating machine. Reference numeral 3 identifies the sheet or web of material to be dehydrated or freed from water. The sheet of material 3 passes first through the wet portion or station A in which the water is suctioned off, and then arrives in the registering portion or station E in which a first squeezing out of the moisture takes place between pairs of rollers. Thereafter the material passes into the preliminary squeezing or pressing station C where a further squeezing out of the water takes place between pairs of rollers. In the adjacent main squeezing portion of station D, the liquid is squeezed out between two rollers, with a great amount of pressure, up to an admissible residual part.

In FIG. 2, the upper rollers of the roller pairs of the preliminary squeezing or pressing station C have been identified with reference numeral 6, and the lower rollers have been identified with reference numeral 7. The axles of the upper rollers 6 are rigidly positioned, and

I the axles of the lower rollers 7 are positioned in a bar 8. This bar 8 has a pivot axis 9 which is offset with respect to the center of gravity'of the axles of the lower rollers 7 and from the center of the bar 8, in the traveling or operating direction of the sheet of material 3 and the sieves l and 2, as indicated by the arrow 10. Upon this pivot axis 9 acts the arm 11 of a double-armed rocking lever 12, which is pivotal about a pivot axis 14 which is stationary within the frame 13, and whose other lever arm 15 is supported against the frame 13 with the interposition of a pressing-on means 16. This It will be obvious to those skilledin the art that many modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications.

What is claimed is:

1. In a pressing device for the removal of water from solid materials comprising a plurality of pairs of rollers, consisting of upper and lower horizontally disposed rolv lers, respectively, spaced from one another along the direction of travel of the material to be dehydrated through said pressing device and between which said material to be dehydrated is passed on a sieve or between two sieves and common bar means supporting at least a part of said rollers on one side of said sieve, the improvement comprising pivot means supporting said bar means and through which pressure is applied to said bar means toward said sieve and which is mounted on said bar means between the first and last of said rollers supported by said bar means and offset from and forward, with respect to the direction of travel of said material to be dehydrated through said pressing device, of the center of gravity of said bar means and said rollers supported by said bar means.

2. A device in accordance with claim 1 wherein the pressing device is a device for the removal of water from a sheet or web of cellulose or similar fibrous material and the rollers supported by the bar means are in a preliminary pressing station of said device.

3. A device in accordance with claim 2 wherein all of the rollers in the preliminary pressing station are supported by the bar means.

4. A device in accordance with claim 1 wherein the lower rollers are mounted in the bar means and the upper rollers complementary thereto are rigidly mounted.

5. A device in accordance with claim 4 wherein the lower rollers are adjustable with respect to the upper rollers.

6. A device in accordance with claim 1 wherein the pivot means is mounted on one end of an arm means means in a direction away from the sieve.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 79 6 149 Dated March 12 1974- Invent'or (s) Otto Heissenberger It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

The following should be added to the cover page:

[Bil Foreign Application Priority Data April 5 1971 Austria 2891/71 Signed and sealed this 9th day of July 1974.

(SEAL) Attest:

McCOY M. GIBSON JR. C. MARSHALL -DANN Attesting Officer Commissioner of Patents F R 0-1O50 (10-69) USCOMM-DC 60376-P69 k U.S. GOVERNMENT PRINTING OFFICE I99 0-356-33]. 

1. In a pressing device for the removal of water from solid materials comprising a plurality of pairs of rollers, consisting of upper and lower horizontally disposed rollers, respectively, spaced from one another along the direction of travel of the material to be dehydrated through said pressing device and between which said material to be dehydrated is passed on a sieve or between two sieves and common bar means supporting at least a part of said rollers on one side of said sieve, the improvement comprising pivot means supporting said bar means and through which pressure is applied to said bar means toward said sieve and which is mounted on said bar means between the first and last of said rollers supported by said bar means and offset from and forward, with respect to the direction of travel of said material to be dehydrated through said pressing device, of the center of gravity of said bar means and said rollers supported by said bar means.
 2. A device in accordance with claim 1 wherein the pressing device is a device for the removal of water from a sheet or web of cellulose or similar fibrous material and the rollers supported by the bar means are in a preliminary pressing station of said device.
 3. A device in accordance with claim 2 wherein all of the rollers in the preliminary pressing station are supported by the bar means.
 4. A device in accordance with claim 1 wherein the lower rollers are mounted in the bar means and the upper rollers complementary thereto are rigidly mounted.
 5. A device in accordance with claim 4 wherein the lower rollers are adjustable with respect to the upper rollers.
 6. A device in accordance with claim 1 wherein the pivot means is mounted on one end of an arm means and said arm means is mounted on a fixedly mounted second pivot means.
 7. A device in accordance with claim 6 wherein the second pivot means is located intermediate the ends of the arm means.
 8. A device in accordance with claim 7 wherein pressure is applied through the first pivot means by pressure means operatively acting on the free end of the arm means in a direction away from the sieve. 